Scientists tease the brain to give up its secrets

The modern metaphor for the brain is a computer, but that hardly begins to capture how extraordinary the human brain is. Just take one example—what Martha Farah, professor of psychology and director of the Center for Cognitive Neuroscience calls “knowledge systems.”

“I could ask you what you know about, for example fire regulations, to pick an obscure topic,” explained Farah, “and you would be able to tell me something. How is that knowledge represented in your brain? How is it so accessible? This is the holy grail of artificial intelligence, but we do it easily, all the time.”

The Center for Cognitive Neuroscience, a multidisciplinary group of researchers, was formed in 1999 to research the neural basis of human thought. The Center has eight core faculty in neurology, psychiatry and psychology housed in half a rowhouse at 3815 Walnut Street, and 27 affiliated faculty from all over the University.

“In the possibly biased opinions of some of us, the mind sciences are the most exciting branch of science at the turn of the 21st century,” said Farah. “For the first time, we have some powerful new techniques for probing human brain function—probing the kind of brain functions that are relevant to cognition—to thinking, not just seeing and eating and other lower functions. We have enough of a theoretical framework to begin asking the right questions. The science is poised for revolutionary progress.”

Penn is a major center for brain research. “One of the reasons that CCN has thrived,” said Farah, “is that there is fantastic bench neuroscience here, strong neuro-imaging within radiology and state-of-the-art clinical neuroscience at the Brain Behavior Laboratory [directed by Professor of Psychology Ruben Gur] on illnesses like schizophrenia.”

Penn is also methodologically diverse. “It is easy to become a slave to your equipment,” Farah maintained. “We start by asking good questions and then decide which method is best for finding that answer whether it is functional magnetic resonance imaging, brainwaves using electrodes, converging evidence from patients or subjects [frequently psychology undergraduates Farah calls ‘Pennus sophmorus’], computational modeling or behaviorial methods.”

Within the Center there are specific research programs on memory, attention, which Farah describes as “holding something in your mind while you are working on it—like doing math problems in your head,” emotion and mood, and vision.

Recent work by Psychology Professor Russell Epstein has uncovered new information about how the brain solves the problem of recognition. “We know from brain scans that there is no general-purpose recognizer,” said Farah. “It recognizes faces differently than it recognizes chairs. Epstein found that anything that we would label with the English word ‘place,’ like an interior or landscape, activates a specific region of the brain that is, interestingly, right on the boundary between visual areas and memory areas.”

Brain researchers started out asking how does a typical brain work and how do pathological states deviate from the norm. “Now we are just starting to look at the cognitive neuroscience of individuality,” said Farah. We are asking how, within a normal population, do people differ. What makes you a great architect or a talented musician or love children? I think this is most interesting on the human level.”

Originally published on November 13, 2003